1.You can use the timer to SWITCH ON/OFF any electrical equipments at a preset timer 2.16 ON/OFF programs per day, 15 combinations to a week. 24 hours / a week programmable. 3. Built-in battery for backup the memory (save the programs you set)when power failure 4. Auto time error correction +/- 30 sec, weekly 5. Repeat programs with 16 on/off , and setting on/off manually, Easy to read LCD display, LED indicators. PROGRMMALBE TIMER SWITCH HAS FUNCTIONS: 1. CLOCK DISPLAY 2. TIMER 3. COUNTDOWN 4. AUTO TIME DEFLECTION CORRECTION, WEEKLY 5. SLEEP MODE Usage: The TM618 timer MODULE (1.598INCH big LCD display) can open or kinds of electrical apparatus and power automatically, according to the preset time, the items can be streetlight, light (sign), , electrical appliances, broadcast equipments etc., the digital timer switch is within rechargeable battery, in 1.2V/40Ma, high-accuracy CMOS chip, strongly anti-jamming, easy to use. size:7.0 cm x 7.0 cm x 4.0 cm Material:ABS+electronic components colour:white Package Contents: 1 x TM618N-4 switch 1 x Manual Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.